/Engine/Source/Runtime/SignalProcessing/Public/DSP/AllPassFractionalDelay.h
InMaxDelay sets the maximum allowable delay that this object can support. The minimum delay is 0.5 InNumInternalBufferSamples sets the maximum block processing size.
FAllPassFractionalDelay ( int32 InMaxDelay, int32 InNumInternalBufferSamples )